A lithium-ion secondary battery includes therein a positive electrode and a negative electrode which are separated by a porous separator. In production of lithium ion secondary batteries, a separator roll is used. The separator roll is obtained by winding this separator around a core having a cylindrical shape. The separator roll has a hollow core, into which a core member is inserted to form an assembly for transport or storage.
(a) of FIG. 17 is a diagram illustrating a configuration of a conventional assembly. As illustrated in (a) of FIG. 17, an assembly 260 includes a plurality of separator rolls 210 and a pillar-shaped core member 230 extending through the respective axis holes 208a of the separator rolls 210. The core member 230 has opposite ends each fitted with a protector 220. The protectors 220 each have a plate shape and have an opening at a central portion. The opposite ends of the core member 230 are each inserted into the opening of a protector 220 so that the core member 230 is supported by the protectors 220.
Patent Literature 1 discloses a packaging apparatus that automatically prepares an assembly by combining a core member with separator rolls and spacers such that the core member is inserted through the separator rolls and the spacers alternately. This packaging apparatus forms an assembly including a plurality of separator rolls and spacers provided therebetween.